diff --git a/inc/DAVResource.php b/inc/DAVResource.php
index c36edf83..fbdbcdf4 100644
--- a/inc/DAVResource.php
+++ b/inc/DAVResource.php
@@ -627,11 +627,37 @@ EOQRY;
     $qry = new AwlQuery('SELECT property_name, property_value FROM property WHERE dav_name= :dav_name', array(':dav_name' => $this->dav_name) );
     if ( $qry->Exec('DAVResource') ) {
       while ( $property = $qry->Fetch() ) {
-        $this->dead_properties[$property->property_name] = $property->property_value;
+        $this->dead_properties[$property->property_name] = self::BuildDeadPropertyXML($property->property_name,$property->property_value);
       }
     }
   }
 
+  public static function BuildDeadPropertyXML($property_name, $raw_string) {
+    if ( !preg_match('{^\s*<.*>\s*$}s', $raw_string) ) return $raw_string;
+    $xmlns = null;
+    if ( preg_match( '{^(.*):([^:]+)$}', $property_name, $matches) ) {
+      $xmlns = $matches[1];
+      $property_name = $matches[2];
+    }
+    $xml = sprintf('<%s%s>%s</%s>', $property_name, (isset($xmlns)?' xmlns="'.$xmlns.'"':''), $raw_string, $property_name);
+    $xml_parser = xml_parser_create_ns('UTF-8');
+    $xml_tags = array();
+    xml_parser_set_option ( $xml_parser, XML_OPTION_SKIP_WHITE, 1 );
+    xml_parser_set_option ( $xml_parser, XML_OPTION_CASE_FOLDING, 0 );
+    $rc = xml_parse_into_struct( $xml_parser, $xml, $xml_tags );
+    if ( $rc == false ) {
+      dbg_error_log( 'ERROR', 'XML parsing error: %s at line %d, column %d',
+                  xml_error_string(xml_get_error_code($xml_parser)),
+                  xml_get_current_line_number($xml_parser), xml_get_current_column_number($xml_parser) );
+      dbg_error_log( 'ERROR', "Error occurred in:\n%s\n",$xml);
+      return $raw_string;
+    }
+    xml_parser_free($xml_parser);
+    $position = 0;
+    $xmltree = BuildXMLTree( $xml_tags, $position);
+    $content = $xmltree->GetContent();
+    return $content[0];
+  }
 
   /**
   * Build permissions for this URL
diff --git a/inc/Principal.php b/inc/Principal.php
index aeb25230..b40b7699 100644
--- a/inc/Principal.php
+++ b/inc/Principal.php
@@ -398,7 +398,7 @@ class Principal {
     $qry = new AwlQuery('SELECT property_name, property_value FROM property WHERE dav_name= :dav_name', array(':dav_name' => $this->dav_name()) );
     if ( $qry->Exec('Principal') ) {
       while ( $property = $qry->Fetch() ) {
-        $this->dead_properties[$property->property_name] = $property->property_value;
+        $this->dead_properties[$property->property_name] = DAVResource::BuildDeadPropertyXML($property->property_value);
       }
     }
   }
diff --git a/inc/caldav-MKCOL.php b/inc/caldav-MKCOL.php
index ea82aef1..261f3d86 100644
--- a/inc/caldav-MKCOL.php
+++ b/inc/caldav-MKCOL.php
@@ -65,8 +65,8 @@ if ( isset($request->xml_tags) ) {
 
   foreach( $setprops AS $k => $setting ) {
     $tag = $setting->GetNSTag();
-    $content = $setting->RenderContent();
-
+    $content = $setting->RenderContent(0,null,true);
+    
     dbg_error_log( 'MKCOL', 'Processing tag "%s"', $tag);
 
     switch( $tag ) {
diff --git a/inc/caldav-PROPPATCH.php b/inc/caldav-PROPPATCH.php
index a6ddb5de..1daebb8c 100644
--- a/inc/caldav-PROPPATCH.php
+++ b/inc/caldav-PROPPATCH.php
@@ -79,7 +79,7 @@ $qry->Begin();
 $setcalendar = count($xmltree->GetPath('/DAV::propertyupdate/DAV::set/DAV::prop/DAV::resourcetype/urn:ietf:params:xml:ns:caldav:calendar'));
 foreach( $setprops AS $k => $setting ) {
   $tag = $setting->GetNSTag();
-  $content = $setting->RenderContent();
+  $content = $setting->RenderContent(0,null,true);
 
   switch( $tag ) {
 
@@ -113,18 +113,39 @@ foreach( $setprops AS $k => $setting ) {
       * We only allow resourcetype setting on a normal collection, and not on a resource, a principal or a bind.
       * Only collections may be CalDAV calendars or addressbooks, and they may not be both.
       */
-      $setcollection  = count($setting->GetPath('DAV::resourcetype/DAV::collection'));
-      $setaddressbook = count($setting->GetPath('DAV::resourcetype/urn:ietf:params:xml:ns:carddav:addressbook'));
-      if ( $dav_resource->IsCollection() && $setcollection && ! $dav_resource->IsPrincipal()
-                            && ! $dav_resource->IsBinding() && ! ($setaddressbook && $setcalendar) ) {
-        $resourcetypes = $setting->GetPath('DAV::resourcetype/*');
-        $resourcetypes = str_replace( "\n", "", implode('',$resourcetypes));
+      $resourcetypes = $setting->GetPath('DAV::resourcetype/*');
+      $setcollection = false;
+      $setcalendar = false;
+      $setaddressbook = false;
+      $setother = false;
+      foreach( $resourcetypes AS $xnode ) {
+        switch( $xnode->GetNSTag() ) {
+          case 'urn:ietf:params:xml:ns:caldav:calendar':      $setcalendar = true;      break;
+          case 'urn:ietf:params:xml:ns:carddav:addressbook':  $setaddressbook = true;   break;
+          case 'DAV::collection': $setcollection = true; break;
+          default:
+            $setother = true;
+        }
+      }
+      if ( $dav_resource->IsCollection() && $setcollection && ! $dav_resource->IsPrincipal() && ! $dav_resource->IsBinding()
+          && !($setcalendar && $setaddressbook) && !$setother ) {
+        $resourcetypes = '<collection xmlns="DAV:"/>';
+        if ( $setcalendar ) $resourcetypes .= '<calendar xmlns="urn:ietf:params:xml:ns:caldav"/>';
+        else if ( $setaddressbook ) $resourcetypes .= '<addressbook xmlns="urn:ietf:params:xml:ns:carddav"/>';
         $qry->QDo('UPDATE collection SET is_calendar = :is_calendar::boolean, is_addressbook = :is_addressbook::boolean,
                      resourcetypes = :resourcetypes WHERE dav_name = :dav_name',
                     array( ':dav_name' => $dav_resource->dav_name(), ':resourcetypes' => $resourcetypes,
                            ':is_calendar' => $setcalendar, ':is_addressbook' => $setaddressbook ) );
         $success[$tag] = 1;
       }
+      else if ( $setcalendar && $setaddressbook ) {
+        add_failure('set', $tag, 'HTTP/1.1 409 Conflict',
+            translate("A collection may not be both a calendar and an addressbook."));
+      }
+      else if ( $setother ) {
+        add_failure('set', $tag, 'HTTP/1.1 403 Forbidden',
+             translate("Unsupported resourcetype modification."), 'cannot-modify-protected-property');
+      }
       else {
         add_failure('set', $tag, 'HTTP/1.1 403 Forbidden',
              translate("Resources may not be changed to / from collections."), 'cannot-modify-protected-property');